The Marshall TSL and DSL are great sounding amps. I have owned a couple, but after been bitten, Im twice shy.
$$$$$$$$$$$$$$$$$$$ and lots of $$$$$$$$$$$$$$$$$
Marshall TSD/DSL repair info
I first discovered the issues with the Marshall TSL series of amps as I owned a couple
I had a TSL122 and later a TSL100
A warning about repairing theses amps.
I don’t want to go on for pages and pages so I will keep to the basics
If you red plate or destroy power output tubes, or you clean channel has a hum that starts off quiet and gets louder as the amp gets warmer, be prepared for a mega repair bill.
These are symptoms of a defective main board, the boards that houses the power tubes and preamp tubes.
The board material breaks down and they start to track the high volts.
Bottom line prices.
I use to offer a workaround but after a recent repair I no longer offer this repair
A new main board last time my price from the Australian importer was $450
It takes about a 1.5 hour to repair
and will require a set of power tubes
So you are looking at prices starting from $830 (this usually covers it)
If you have also blown a power transformer add another $300
I know all about the mods, as I was active in the early days in the development of such mods.
Yes they can buy you time, but unfortunately the issues will arise in the clean channel, and so on.
https://drtube.com/en/modifications/jcm2000-stable-bias-mod
he does a really nice mod kit, but unfortunately it does not solve the problem with the Clean channel Hum problem.
My advise is to right the amp off or except the expensive repair bill.
They are a great sounding amp, they are repairable with new boards at the moment in 2018.
TSL100/ DSL100/ TSL100 main board
Checking bias drift
Insulation test of PCB between control grid and adjacent pins showing a dramatic leakage.
http://www.lynx.net/~jc/TSL122.html (a great info page)
